X-Git-Url: http://repo.macrolet.net/gitweb/?a=blobdiff_plain;f=src%2Fcompiler%2Fknownfun.lisp;h=ee94ecdd572a73cce26fa0e9b1ff75e5ffb89bca;hb=34dd23563d2f5cf05c72b971da0d0b065a09bf2a;hp=d80d29969fa6586dd19b26c57de7059d3095abef;hpb=6e7e59adb6f6c30f84b31695b48cb51e2c519d75;p=sbcl.git diff --git a/src/compiler/knownfun.lisp b/src/compiler/knownfun.lisp index d80d299..ee94ecd 100644 --- a/src/compiler/knownfun.lisp +++ b/src/compiler/knownfun.lisp @@ -1,6 +1,6 @@ ;;;; This file contains stuff for maintaining a database of special ;;;; information about functions known to the compiler. This includes -;;;; semantic information such as side-effects and type inference +;;;; semantic information such as side effects and type inference ;;;; functions as well as transforms and IR2 translators. ;;;; This software is part of the SBCL system. See the README file for @@ -18,87 +18,93 @@ ;;; IR1 boolean function attributes ;;; -;;; There are a number of boolean attributes of known functions which we like -;;; to have in IR1. This information is mostly side effect information of a -;;; sort, but it is different from the kind of information we want in IR2. We -;;; aren't interested in a fine breakdown of side effects, since we do very -;;; little code motion on IR1. We are interested in some deeper semantic -;;; properties such as whether it is safe to pass stack closures to. +;;; There are a number of boolean attributes of known functions which +;;; we like to have in IR1. This information is mostly side effect +;;; information of a sort, but it is different from the kind of +;;; information we want in IR2. We aren't interested in a fine +;;; breakdown of side effects, since we do very little code motion on +;;; IR1. We are interested in some deeper semantic properties such as +;;; whether it is safe to pass stack closures to. (def-boolean-attribute ir1 - ;; May call functions that are passed as arguments. In order to determine - ;; what other effects are present, we must find the effects of all arguments - ;; that may be functions. + ;; may call functions that are passed as arguments. In order to + ;; determine what other effects are present, we must find the + ;; effects of all arguments that may be functions. call - ;; May incorporate function or number arguments into the result or somehow - ;; pass them upward. Note that this applies to any argument that *might* be - ;; a function or number, not just the arguments that always are. + ;; may incorporate function or number arguments into the result or + ;; somehow pass them upward. Note that this applies to any argument + ;; that *might* be a function or number, not just the arguments that + ;; always are. unsafe - ;; May fail to return during correct execution. Errors are O.K. + ;; may fail to return during correct execution. Errors are O.K. unwind - ;; The (default) worst case. Includes all the other bad things, plus any - ;; other possible bad thing. If this is present, the above bad attributes - ;; will be explicitly present as well. + ;; the (default) worst case. Includes all the other bad things, plus + ;; any other possible bad thing. If this is present, the above bad + ;; attributes will be explicitly present as well. any - ;; May be constant-folded. The function has no side effects, but may be - ;; affected by side effects on the arguments. e.g. SVREF, MAPC. Functions - ;; that side-effect their arguments are not considered to be foldable. - ;; Although it would be "legal" to constant fold them (since it "is an error" - ;; to modify a constant), we choose not to mark these functions as foldable - ;; in this database. + ;; may be constant-folded. The function has no side effects, but may + ;; be affected by side effects on the arguments. e.g. SVREF, MAPC. + ;; Functions that side-effect their arguments are not considered to + ;; be foldable. Although it would be "legal" to constant fold them + ;; (since it "is an error" to modify a constant), we choose not to + ;; mark these functions as foldable in this database. foldable - ;; May be eliminated if value is unused. The function has no side effects - ;; except possibly CONS. If a function is defined to signal errors, then it - ;; is not flushable even if it is movable or foldable. + ;; may be eliminated if value is unused. The function has no side + ;; effects except possibly CONS. If a function is defined to signal + ;; errors, then it is not flushable even if it is movable or + ;; foldable. flushable - ;; May be moved with impunity. Has no side effects except possibly CONS, and - ;; is affected only by its arguments. + ;; may be moved with impunity. Has no side effects except possibly + ;; consing, and is affected only by its arguments. movable - ;; Function is a true predicate likely to be open-coded. Convert any - ;; non-conditional uses into (IF T NIL). + ;; The function is a true predicate likely to be open-coded. Convert + ;; any non-conditional uses into (IF T NIL). predicate - ;; Inhibit any warning for compiling a recursive definition. (Normally the - ;; compiler warns when compiling a recursive definition for a known function, - ;; since it might be a botched interpreter stub.) + ;; Inhibit any warning for compiling a recursive definition. + ;; (Normally the compiler warns when compiling a recursive + ;; definition for a known function, since it might be a botched + ;; interpreter stub.) recursive - ;; Function does explicit argument type checking, so the declared type should - ;; not be asserted when a definition is compiled. + ;; The function does explicit argument type checking, so the + ;; declared type should not be asserted when a definition is + ;; compiled. explicit-check) (defstruct (fun-info #-sb-xc-host (:pure t)) - ;; Boolean attributes of this function. + ;; boolean attributes of this function. (attributes (missing-arg) :type attributes) - ;; A list of Transform structures describing transforms for this function. + ;; TRANSFORM structures describing transforms for this function (transforms () :type list) - ;; A function which computes the derived type for a call to this function by - ;; examining the arguments. This is null when there is no special method for - ;; this function. + ;; a function which computes the derived type for a call to this + ;; function by examining the arguments. This is null when there is + ;; no special method for this function. (derive-type nil :type (or function null)) - ;; A function that does various unspecified code transformations by directly - ;; hacking the IR. Returns true if further optimizations of the call - ;; shouldn't be attempted. + ;; a function that does various unspecified code transformations by + ;; directly hacking the IR. Returns true if further optimizations of + ;; the call shouldn't be attempted. ;; - ;; KLUDGE: This return convention (non-NIL if you shouldn't do further - ;; optimiz'ns) is backwards from the return convention for transforms. - ;; -- WHN 19990917 + ;; KLUDGE: This return convention (non-NIL if you shouldn't do + ;; further optimiz'ns) is backwards from the return convention for + ;; transforms. -- WHN 19990917 (optimizer nil :type (or function null)) - ;; If true, a special-case LTN annotation method that is used in place of the - ;; standard type/policy template selection. It may use arbitrary code to - ;; choose a template, decide to do a full call, or conspire with the - ;; IR2-Convert method to do almost anything. The Combination node is passed - ;; as the argument. + ;; If true, a special-case LTN annotation method that is used in + ;; place of the standard type/policy template selection. It may use + ;; arbitrary code to choose a template, decide to do a full call, or + ;; conspire with the IR2-Convert method to do almost anything. The + ;; Combination node is passed as the argument. (ltn-annotate nil :type (or function null)) - ;; If true, the special-case IR2 conversion method for this function. This - ;; deals with funny functions, and anything else that can't be handled using - ;; the template mechanism. The Combination node and the IR2-Block are passed - ;; as arguments. + ;; If true, the special-case IR2 conversion method for this + ;; function. This deals with funny functions, and anything else that + ;; can't be handled using the template mechanism. The Combination + ;; node and the IR2-Block are passed as arguments. (ir2-convert nil :type (or function null)) - ;; A list of all the templates that could be used to translate this function + ;; all the templates that could be used to translate this function ;; into IR2, sorted by increasing cost. (templates nil :type list) - ;; If non-null, then this function is a unary type predicate for this type. + ;; If non-null, then this function is a unary type predicate for + ;; this type. (predicate-type nil :type (or ctype null)) - ;; If non-null, use this function to annotate the known call for the byte - ;; compiler. If it returns NIL, then change the call to :full. + ;; If non-null, use this function to annotate the known call for the + ;; byte compiler. If it returns NIL, then change the call to :full. (byte-annotate nil :type (or function null))) (defprinter (fun-info) @@ -123,8 +129,8 @@ ;; sbcl-0.pre7.54 or so, that's inconsistent with being a ;; FUN-TYPE.) (type (missing-arg) :type ctype) - ;; the transformation function. Takes the COMBINATION node and returns a - ;; lambda, or throws out. + ;; the transformation function. Takes the COMBINATION node and + ;; returns a lambda expression, or throws out. (function (missing-arg) :type function) ;; string used in efficiency notes (note (missing-arg) :type string) @@ -227,17 +233,17 @@ (when cont (continuation-type cont)))) ;;; Derive the result type according to the float contagion rules, but -;;; always return a float. This is used for irrational functions that preserve -;;; realness of their arguments. +;;; always return a float. This is used for irrational functions that +;;; preserve realness of their arguments. (defun result-type-float-contagion (call) (declare (type combination call)) (reduce #'numeric-contagion (combination-args call) :key #'continuation-type :initial-value (specifier-type 'single-float))) -;;; Return a closure usable as a derive-type method for accessing the N'th -;;; argument. If arg is a list, result is a list. If arg is a vector, result -;;; is a vector with the same element type. +;;; Return a closure usable as a derive-type method for accessing the +;;; N'th argument. If arg is a list, result is a list. If arg is a +;;; vector, result is a vector with the same element type. (defun sequence-result-nth-arg (n) (lambda (call) (declare (type combination call))